This invention relates to telephony and, more particularly, to conferencing. Further, this invention related to arrangements where a data network is employed in conjunction with to the conventional public switched telephone network (PSTN).
Conferencing a group of participants is not new. Such conferencing is typically accomplished by bridging a number of calls at a single point, that point being local to one of the conferees, or within the telephone network.
The use of a packet network in conjunction with the PSTN is also not new. The ROSE service, offered by AT&T, provides a virtual telephonic presence through an arrangement such as the one depicted in FIG. 1. In office 10, a user's business telephone 11 is connected to a central office in Public Switched Telephone Network (PSTN) 100 through PBX 50. At a remote location, such at home 30, a telephone 32 is connected to (perhaps a different) a central office in PSTN 100, and a computer 31 (which may be a PC) is connected to digital network 200 (e.g., the Internet) through an encryption/decryption circuit 33. PC 31 is connected through network 200 to coupler 25 that includes a processor 20, and encryption/decryption circuit 21. More specifically, coupler 25 has two ports, with one connected to digital control port 51 of PBX 50, and the other connected to network 200. Processor 20 interacts with signals of port 51 directly, and with the signals of the port connected to network 200 via encryption/decryption module 21 (which may be hardware or software). Conventionally, processor 20 includes memory for storing programs and data. The PBX is provisioned to inform port 51 about the state of, and the signals flowing through, the PBX lines that are connected to office telephone 11. Also, port 51 is provisioned to accept control signals relating to the lines that are connected to office telephone 11.
In operation, when a call comes into PBX 50 for office telephone 11 (for example, from telephone 40) and appears on one of the PBX lines that connect to telephone 11 with a ringing signal (for example, line 13), the provisioning in PBX 50 causes the PBX to send a ringing signal message to port 51. Responsive to this signal, processor 20 sends a ringing signal to PC 31 through the path that includes circuit 21, network 200, and circuit 33. Circuit 21 encrypts the message, and circuit 33 decrypts the message so as to maintain privacy of communication between processor 20 and PC 31. There are embodiments of this service without the encryption and decryption phases.
PC 31 includes a “screenphone” application 35 that is adapted to interact with processor 20. This application runs concurrently with whatever other applications computer 31 is asked to run. Application 35 presents an image on the screen of PC 31 that includes telephone 11, each of the lines that connect telephone 11 to network 100, a “ringer,” a keypad, and various “tools” for commanding different actions. In response to the received ringing signal message, application 35 outputs an alert from PC 31 that shows the specific line that is ringing on telephone 11, which allows an employee to whom telephone 11 is assigned and who is at home in proximity of PC 31 (rather than in office 10), to become aware of the incoming call at office telephone 11. Concurrently with the ringing at application 35, processor 20 requests PBX 50 to redirect, or transfer, the incoming call to telephone 32, and PBX 50 carries out the requested action in a conventional manner. In due course, telephone 32 rings, the employee picks up the phone (knowing that the phone call related to office telephone 11 because application 35 shows telephone 11 ringing) and converses with the user at telephone 40 in the same way that the employee would have done had the employee been in office 10.
By allowing processor 20 to enter control signals that mimic, in their effect, the signals that telephone 11 can present to PBX 50, and conversely, to deliver appropriate messages to PC 31 in response to each control signal that might be applied to the PBX lines that connect to telephone 11, the environment of office 10 can be emulated in home 30.
Of course, the FIG. 1 arrangement is dependent on having a PBX.
In patent application Ser. No. 09/894,173, filed Jul. 20, 2001, I disclosed a system where a virtual presence at an office telephone is realized even in the absence of a PBX connection, as shown in FIG. 2. This is achieved by employing a multi-line telephone that includes a digital port that provides signals in response to changes in the state of the telephone, and which accepts signals that change the state of the telephone. The virtual presence is achieved by connecting the digital port to a local processor that interacts with an application on a remote computer that is co-located with a conventional telephone, which telephone can be a single line telephone. The processor is disclosed to be connected the remote computer digital network, and to provide security in applications where the digital network is insecure, encryption and decryption modules are placed on either end of the digital network connection.
In application Ser. No. 08/899,625, filed Jul. 5, 2001, I disclosed a system where a telephone answering system that may have stored messages received from the PSTN can be accessed securely, both for storing messages and for retrieving message by going though an insecure medium such as the public packet network.
A need exists for setting up conferences where, for reasons of delay or economy, one wishes to avoid using local bridging but is willing to employ some processing equipment at each site of the conference.